Serial Data

PCM is equipped with a class 2 serial data line. Serial data is a stream of electrical impulses which can be interpreted by special testers or other control modules. When the ignition switch is turned to RUN position, each module sends a State Of Health (SOH) message to the other modules using the serial data line. Ensuring the modules are working properly. If a module stops communicating, other control modules expecting information from that module will set a DTC. Serial data and codes must be accessed using a scan tool connected to the Data Link Connector (DLC). Note that a loss of serial data DTC does not normally represent a failure of the module that set it.